The separation of mixed signals is a common problem in wireless communications, particularly in urban environments in which many signal sources (such as mobile phones and personal digital assistants, for example) are transmitting and receiving wireless communications. Often the number of signal sources exceeds the number of sensors, or antenna elements, which receive the wireless signals from such signal sources. This is commonly referred to as an overloaded case, or an overloaded antenna array. Current techniques which attempt to separate mixed signals in an overloaded case are limited in that they cannot deal well with complex signals, such as multi-path signals, for example. In addition, such techniques are useful only with very small antenna arrays, such as arrays consisting of two elements. Further, antenna arrays often must be calibrated and/or have prior knowledge of the particular wireless signals within the relevant wireless environment.
Thus, there is a need for systems and methods that can separate mixed complex signals into the individual componenet source signals in an overloaded case and for larger antenna arrays. In addition, it would be advantageous for such systems and methods to act in a “blind” manner—in other words, without having prior knowledge of the wireless signals within the relevant wireless environment.